Summary:
SECONDARY SERVICE RESERVOIR AIR CHECK VALVES MAY NOT SEAT PROPERLY DUE TO A MECHANICAL INTERFERENCE CONDITION BETWEEN A CIRCULAR BRASS GUIDE AND THE WALL OF A CYLINDRICAL FERRULE IN WHICH THE BRASS GUIDE IS INTENDED TO MOVE FREELY.

Consequence:
IN THE EVENT OF PRESSURE LOSS IN THE SUPPLY RESERVOIR,A DEFECTIVE CHECK VALVE WOULD ALLOW PRESSURE EQUALIZATION BETWEEN PRIMARY ANDSECONDARY SERVICE RESERVOIRS, PRESENTING THE POTENTIAL FOR LOSS OR ABSENCE OFFRONT BRAKING ABILITY, WHICH COULD CAUSE LOSS OF CONTROL AND AN ACCIDENT.